* Fix clippy lint in test. Use suggestion

* Widen acceptable versions of hashbrown
* Use conditional compilation to choose more efficient implementation
  This allows rust 1.70 but gives no perf penalty for 1.75.
  There may well be another way around CI failure.

crates/oq3_lexer/src/tests.rs

@@ -4,13 +4,13 @@
 use super::*;
 
 use expect_test::{expect, Expect};
+use std::fmt::Write;
 
-// FIXME: Probably do what clippy asks for here
-#[allow(clippy::format_collect)]
 fn check_lexing(src: &str, expect: Expect) {
-    let actual: String = tokenize(src)
-        .map(|token| format!("{:?}\n", token))
-        .collect();
+    let actual: String = tokenize(src).fold(String::new(), |mut output, token| {
+        let _ = writeln!(output, "{token:?}");
+        output
+    });
     expect.assert_eq(&actual)
 }
 

crates/oq3_semantics/Cargo.toml

@@ -17,7 +17,7 @@ doctest = false
 [dependencies]
 oq3_source_file.workspace = true
 oq3_syntax.workspace = true
-hashbrown = { version = "0.14" }
+hashbrown = { version = "0.12.3" }
 rowan = "0.15.11"
 boolenum = "0.1"
 

crates/oq3_syntax/Cargo.toml

@@ -27,6 +27,7 @@ smol_str = "0.2.0"
 stdx = { version = "0.0.188", package = "ra_ap_stdx"}
 triomphe = { version = "0.1.8", default-features = false, features = ["std"] }
 xshell = "0.2.2"
+rustversion = "1.0"
 # local crates
 oq3_lexer.workspace = true
 oq3_parser.workspace = true

crates/oq3_syntax/src/ptr.rs

@@ -32,6 +32,14 @@ pub struct AstPtr<N: AstNode> {
 }
 
 impl<N: AstNode> Clone for AstPtr<N> {
+    #[rustversion::before(1.74)]
+    fn clone(&self) -> AstPtr<N> {
+        AstPtr {
+            raw: self.raw.clone(),
+            _ty: PhantomData,
+        }
+    }
+    #[rustversion::since(1.74)]
     fn clone(&self) -> AstPtr<N> {
         AstPtr {
             raw: self.raw,
@@ -67,10 +75,16 @@ impl<N: AstNode> AstPtr<N> {
         N::cast(syntax_node).unwrap()
     }
 
+    #[rustversion::since(1.74)]
     pub fn syntax_node_ptr(&self) -> SyntaxNodePtr {
         self.raw
     }
 
+    #[rustversion::before(1.74)]
+    pub fn syntax_node_ptr(&self) -> SyntaxNodePtr {
+        self.raw.clone()
+    }
+
     pub fn text_range(&self) -> TextRange {
         self.raw.text_range()
     }